1. Field of the invention
The invention relates generally to a color translation method and a color translation apparatus, and more particularly to a color translation method and a color translation apparatus capable of mitigating the color shift phenomenon.
2. Description of Related Art
Color has the capability to represent information because it is recognizable to human vision. As technology advances, color control has become an important aspect during the process of making images and photos on different mediums. Typically speaking, in order to accurately formulate the needed colors, a color model is used to generate the required colors, such as the red-green-blue (RGB) color model or the cyan-magenta-yellow-black (CMYK) color model. For a specific color model, a mapping function or a coordinate range is given to construct a color space.
Since different mediums may have different physical properties and different equipments are used, etc., various degrees of display capabilities are exhibited, such that the suitable color space for each medium is different. Even if two color spaces are established on the same color model, differences may arise due to the varying color gamuts. Therefore, when mapping one color space to another color space (i.e. color translation), a corresponding gamut mapping operation needs to be performed.
However, if the original color space has large amounts of colors (i.e., large amounts of coordinates need to be mapped to the new color space), then the mapped points in the new color space which need to be recorded would correspondingly increase. Therefore, a common method is to only record the important mapped points and use an interpolation operation to search for the mapped points in the new color space of the coordinates of the original color space. However, if only the three primary color axes (e.g., the red, green, and blue axes in the RGB color model) are used for the interpolation operation, then relative to the coordinates of the original color space, a color shift phenomenon would likely occur on the color axes (e.g. magenta and gray axes) other than the three primary colors. Therefore, researchers in the field are investigating how to avoid the color shift phenomenon when performing gamut mapping.